1. Field of the Invention
The present invention relates to a lens case for transporting a light-weight, small-sized lens; and, in particular, to a lens case for transporting a plastic lens employed, for example, in a pickup optical system for reading out information recorded in a CD, DVD, or the like.
2. Related Background Art
Conventionally, a small-sized, lightweight lens is employed in a pickup optical system for reading out information recorded in a recording medium such as a CD, DVD, or the like. The lens is made of a plastic into a diameter of about several millimeters. FIG. 8 shows an example of such a lens. The lens 10 shown in FIG. 8 is made by injection molding of an acrylic resin or the like. The center of the lens 10 is formed with an optically functioning part 10a which functions as an optical lens. The outer peripheral part of the optically functioning part 10a is formed with a flange 10b having a flat part 10c which functions as a base surface when the lens is mounted to a pickup optical system (not depicted). Also, the flat part 10c projects beyond the surface (lens face) of the optically functioning part 10a along the optical axis direction of the lens 10, so that the flange 10b functions to protect the optically functioning part 10a.
Upon shipping or the like, such a lens is transported while being accommodated in a lens case such as that shown in FIG. 9. The lens case 101 shown in FIG. 9 comprises a case main body 102. The case main body 102 is formed like an elongated pipe and has an inner space 103 for accommodating the lens 10. The case main body 102 is manufactured by extruding a synthetic resin. The inner space 103 has a quadrangular cross section. When being transported, the lens 10 is accommodated within the inner space 103 of the case main body 102. The flat part 10c of the flange 10b comes into contact with inner faces 104a and 105a of upper and lower walls 104 and 105 which form the inner space 103. In the lens case 101, a number of lenses 10 are accommodated with some play along the longitudinal direction of the case main body 102.
The above-mentioned conventional lens case, however, has the following problems. Namely, it has been difficult to take out the lenses from the lens case. Also, dust and dirt are likely to stick to and hard to remove from the lenses taken out from the lens case.